As lawmakers and agency officials look to accelerate the deployment of mobile broadband networks, broadcasters circle the wagons in defense of their airwaves.

The head of the lobbying arm of the broadcast industry is calling on the White House to put the brakes on efforts to wrest wireless spectrum away from its members for use in new mobile broadband networks.

In a letter to Lawrence Summers, President Obama's top economic advisor, Gordon Smith, the president and CEO of the National Association of Broadcasters (NAB), warned against legislative and regulatory proposals that would undercut free, over-the-air television transmissions.

The FCC's proposal, put forward in the national broadband plan released in March, calls for the reallocation of 500 MHz of spectrum from government and commercial users over the next 10 years. Of that, the FCC said that 120 MHz should come from broadcasters, suggesting that the government sell off the spectrum in "incentive auctions" that would return a share of the proceeds to the license holders that relinquished their portions of the airwaves.

In response, the NAB has warned that the FCC's proposal could see its members forced to give up their licenses and go off the air, despite the assurances from the agency that participation in the auctions will be voluntary.

"As we have discussed, we have no quarrel with incentive auctions that are truly voluntary," Smith said in his letter to Summers. "We are concerned, however, that an arbitrary goal of reallocating 120 MHz of spectrum currently designated for broadcast television -- more than 40 percent of the current allotment -- would create a number of serious engineering and practical difficulties."

Smith noted that broadcasters are fresh on the heels of the transition to digital television, a process that saw 108 MHz of spectrum resold in a government auction as they shut down their analog signals, and pointed out that most of those swaths of airwaves have yet to be deployed for mobile broadband networks.

He urged the White House to endorse a set of guiding principles for addressing the spectrum question, including opposition to "onerous new spectrum taxes" levied against broadcasters that choose not to participate in the incentive auctions. In its broadband plan, the FCC had proposed assessing fees to license holders that make inefficient use of their spectrum.

A looming spectrum crisis?

The agency is trying to address what it often describes as a looming spectrum crisis, warning that without a shift in policy, wireless broadband operators will see their networks buckle amid the surging use of Web-enabled mobile devices.

That concern has already caught the attention of lawmakers. On Monday, Sens. John Kerry (D-Mass.) and Olympia Snowe (R-Maine) introduced legislation that would give the FCC the authority to implement the incentive auctions outlined in the broadband plan.

The Spectrum Measurement and Policy Reform Act would trump prior legislative efforts to require the FCC and the National Telecommunications Information Administration, the division of the Commerce Department that oversees government spectrum, to conduct an inventory of the current allocations of spectrum with an eye toward shifting airwaves to mobile broadband. The House has passed a spectrum inventory bill, but the Senate version, also sponsored by Kerry and Snowe, has stalled.

When Summers announced the White House directive in June, he said the administration planned to work with lawmakers to shepherd through legislation to authorize the incentive auctions, and tasked the FCC and NTIA to produce a 10-year plan for reallocating spectrum to mobile broadband by Oct. 1.

The NAB, for its part, continues to caution against compulsory measures to reclaim spectrum from its members. In his letter, Smith touted the efforts broadcasters are making in the digital space, including mobile TV, and argued that positioning the growth of wireless broadband as being at odds with the broadcast industry is a false choice.

"We are hopeful that the administration will continue to recognize broadcasting's undisputed strengths, and that any legislative or regulatory action altering the current spectrum framework will provide Americans with both the finest broadband and broadcast system in the world," he said.